On Thu, May 02, 2024 at 09:55:23AM +0200, Christoph Fritz wrote: > This patch adds a LIN (local interconnect network) bus abstraction on > top of CAN. It is a glue driver adapting CAN on one side while offering > LIN abstraction on the other side. So that upcoming LIN device drivers > can make use of it. > > Tested-by: Andreas Lauser <andreas.lauser@xxxxxxxxxxxxxxxxx> > Signed-off-by: Christoph Fritz <christoph.fritz@xxxxxxxxx> ... > diff --git a/drivers/net/can/lin.c b/drivers/net/can/lin.c ... > +struct lin_device *register_lin(struct device *dev, > + const struct lin_device_ops *ldops) > +{ > + struct net_device *ndev; > + struct lin_device *ldev; > + int ret; > + > + if (!ldops || !ldops->ldo_tx || !ldops->update_bitrate || > + !ldops->ldo_open || !ldops->ldo_stop) { > + netdev_err(ndev, "missing mandatory lin_device_ops\n"); Hi Christoph, The line above uses ndev, but ndev is not initialised until a few lines further down. Flagged by Smatch. > + return ERR_PTR(-EINVAL); > + } > + > + ndev = alloc_candev(sizeof(struct lin_device), 1); > + if (!ndev) > + return ERR_PTR(-ENOMEM); > + > + ldev = netdev_priv(ndev); > + > + ldev->ldev_ops = ldops; > + ndev->netdev_ops = &lin_netdev_ops; > + ndev->flags |= IFF_ECHO; > + ndev->mtu = CANFD_MTU; > + ldev->can.bittiming.bitrate = LIN_DEFAULT_BAUDRATE; > + ldev->can.ctrlmode = CAN_CTRLMODE_LIN; > + ldev->can.ctrlmode_supported = 0; > + ldev->can.bitrate_const = lin_bitrate; > + ldev->can.bitrate_const_cnt = ARRAY_SIZE(lin_bitrate); > + ldev->can.do_set_bittiming = lin_set_bittiming; > + ldev->ndev = ndev; > + ldev->dev = dev; > + > + SET_NETDEV_DEV(ndev, dev); > + > + ret = lin_set_bittiming(ndev); > + if (ret) { > + netdev_err(ndev, "set bittiming failed\n"); > + goto exit_candev; > + } > + > + ret = register_candev(ndev); > + if (ret) > + goto exit_candev; > + > + ldev->lin_ids_kobj = kobject_create_and_add("lin_ids", &ndev->dev.kobj); > + if (!ldev->lin_ids_kobj) { > + netdev_err(ndev, "Failed to create sysfs directory\n"); > + ret = -ENOMEM; > + goto exit_unreg; > + } > + > + ret = lin_create_sysfs_id_files(ndev); > + if (ret) { > + netdev_err(ndev, "Failed to create sysfs entry: %d\n", ret); > + goto exit_kobj_put; > + } > + > + /* Using workqueue as tx over USB/SPI/... may sleep */ > + ldev->wq = alloc_workqueue(dev_name(dev), WQ_FREEZABLE | WQ_MEM_RECLAIM, > + 0); > + if (!ldev->wq) > + goto exit_rm_files; The goto above will result in: return ERR_PTR(ret) But ret is 0 here. Should it be set to a negative error value? Also flagged by Smatch. > + > + INIT_WORK(&ldev->tx_work, lin_tx_work_handler); > + > + netdev_info(ndev, "LIN initialized.\n"); > + > + return ldev; > + > +exit_rm_files: > + lin_remove_sysfs_id_files(ndev); > +exit_kobj_put: > + kobject_put(ldev->lin_ids_kobj); > +exit_unreg: > + unregister_candev(ndev); > +exit_candev: > + free_candev(ndev); > + return ERR_PTR(ret); > +} > +EXPORT_SYMBOL_GPL(register_lin); ...